節頸目

盾皮魚綱的一目.頭部與身體埋墊槳前部均覆蓋有板狀骨甲，頭甲與體甲以關節相譽乃臭提連，上頜和頭可以活恐魚頭胸甲側視及前視動（下贈才只頜不能活動），故名節頸魚.身體較寬大，口及眼均紙頌閥驗大恥棗駝.胸鰭或為不能活動的棘狀，如有腹鰭，一般也較小.生活於淡水或海水，出現於晚志籃習留世，泥盆紀末即滅絕.恐魚為其代表.中國節頸目化石有產於邀祝榆四川中泥盆統的江油魚（Kiangyousteus）、貴州下泥盆統的貴州魚（Kueichowlepis）等.Placodermi of a head. Head and body with the front were covered with a plate of bone, head and body A with A jointconnectedto upper jaw and head can live side-view and the former terrorist head carapace optokinetic (lower jaw is not in ), hence the name section of neck of fish. lenient body, mouth and eyes are large. pectoral fin or the spine is not in shape, if pelvic fins, generally less. live in fresh water or sea water, appeared in the Late Silurian, mud the end of the extermination of basin Ji. fear of the fish as its representative.ChineseFestivalhead neck fossils are produced in Sichuan's Jiangyou Devonian fish (Kiangyousteus), Guizhou, GuizhouLowerDevonian fish (Kueichowlepis) and so on.